Optical character readers (OCRs) have been utilized to correctly recognize and input letters on manuscripts. With the OCR, letters may be input without manual input work using an input device such as a keyboard.
When inputting an English manuscript for instance through manual input work, an operator reads the letters and then manually inputs the read letters through the keyboard. Here, the speed of reading the English manuscript and the input speed through the keyboard largely depend an the linguistic proficiency and the keyboard operating ability of the operator.
In contrast, in the input work with the OCR, the English manuscript is read as graphic information with an optical device such an a scanner. Then, the graphic information is analyzed with a CPU according to a predetermined program, and the information read as graphic image is recognized as a specific character. Since the recognized characters are taken into the device, no manual work is required. Therefore, characters may be input without being affected by the operator's linguistic proficiency or keyboard operating ability.
The OCR can recognize not only characters but also numerals and symbols. Therefore, the OCR is utilized for recognizing postal codes (numerals) on letters or postcards, and checking examination papers (recognizing symbols and numerals) as well as recognizing and inputting characters.
On the other hand, there is an input device such an a pen input device, other than the OCR, with which characters written with a special electronic pen on a liquid crystal screen having transparent electrodes are recognized and input. With the pen input device, input of characters is made upon the characters being written. Therefore, the pen input device requires no separate recognition work with OCR, using a scanner or the like. Also, since no input work through the keyboard is required, the pen input device is attracting attention as a speedy input device.
However, the conventional pen input device has the following problems.
That is to say, since the OCR performs the reading optically, the surface condition of the manuscript on which the characters are written may become a problem. For example, when checking examination papers utilizing the OCR, recognition may not be performed correctly if answering marks such as [O] and [X], or score numerals are overlapped with question sentences.
To avoid such a problem, a scoring box may be provided separately on the answer paper so that the scoring box may be separately recognized with the OCR. In that case, however, the scoring box must always be provided and moreover the reading position must be registered in the OCR. Such preparation work before the recognition work is cumbersome.
Furthermore, the recognition may become uncertain when there are traces of rubber eraser, leaked ink, blurred ink, or breakage or wrinkles on the paper.
Another problem is that, since the checking is followed by the recognition with the OCR, the input work cannot be done speedily in parallel with the checking.
With the pen input device on the other hand, since the data input is done with a special electronic pen, a liquid crystal panel, etc., existing hardware cannot be utilized in the recognition work, and a special computer system is required. This results in a high cost of the product.